1This ABS resin helmet is impact resistance, anticorrosion and wear resistance. So it brings you ear protection and suspension adjustment. 2This water helmet could be used for multi sports, such as water sports, cycling and climbing. It has high practical performance. 3The helmet's inner shell is bonded with highfoam EVA. It is also lighter and more comfortable to wear. 4This outdoor helmet can rotate clockwise to lock and counterclockwise to relax. It can adapt to various head circumferences. 5This water helmet has a total of 11 vent holes. It can effectively dissipate heat and ventilate during your longterm wear. 6This ABS resin helmet has refined appearance and will let you fondle admiringly. Its matte black outlook is filled with features of the times. Item Type: Water Helmet Material: ABS Standard: SGS Testing Standard Purpose: Water Sports/Emergency Assistance Inner Circumference: Approx. 58-64cm/22.8-25.2in Inner Width: Approx. 20-22cm/7.9in-8.7in 1 x Helmet 1 x Storage Bag